What Causes a Push Rod to Bend?

[brownie83]

7.3's don't have timing chains.

How many miles/minutes into it being running did this happen?

i wondered about the chain idea :shocked:

anyway...the first second the key was turned the "cannon" sound started. very scary and loud, but in a perfect rhythm. no smoke, idle seemed fine, but hard to tell with the noise. he was trying to start it due to air from the work, and once the key was turned...bang

 

[HoustonRider]

CHAIN????

lol, I'm throwing **** out there.... :walkin:

 

[Powerstroked162]

You guys use ether to get it to fire?

 

[Magnum PD]

Something wasn't right. Fluid in the cylinder, not set right or something.

 

[brownie83]

Why were the injectors taken out? Valve springs are clear of debri?

yes and yes...injectors were re o-ringed, and new cups were installed, all fluids were mitey vacced, the motor was hand cranked for about 10 revolutions. i assume, the valves seemed clear

 

[brownie83]

You guys use ether to get it to fire?

no...just turned the key

 

[Powerstroked162]

Are you sure you seated the pushrods in the litters? Only thing I can think of is that there was crud in the springs not allowing them to collapse or the pushrod wasn't in the lifter seat.

Fluid in the cylinder, atleast enough to bend pushrods, would've hydrolocked the motor up before it even thought about starting.

 

[Magnum PD]

Hearing the noise after starting it up is a tell-tell sign that something wasn't right. After the injector was put in, maybe oil or fuel leaked in.

 

[brownie83]

maybe it was just installer error...just trying to cover all basis so i have a better understanding. i tried, when helping him fix it the second time, to miss the lifter, and it seems almost impossible...but i didnt install the initial ones. i know when i did mine with the 910 springs, i double and triple checked. its enough to drive you nuts...lol. thanks again for all the help...really appreciate the knowledge. im still a newbie to the diesel work, but have been fixing my own stuff since i can remember

 

[BigAlsPSD]

Chris, did you guys bend another push rod, again? Besides the one at your GTG

 

[brownie83]

Hearing the noise after starting it up is a tell-tell sign that something wasn't right. After the injector was put in, maybe oil or fuel leaked in.

i dont think there was any possible way for fluids to be there...he used a vacuum pump to clean the cylinders and then with the gps out, he turned the motor over numerous times. it actually started after about 4 cycles of trying. he stopped for a while after the sound, but figured...the damage as been done. idled up and there was no smoke at all...just the normal "diesel" idle, but with a huge bang in rhythm...

 

[brownie83]

Chris, did you guys bend another push rod, again? Besides the one at your GTG

no thats the one...but we found out after fixing it sat day, nite and into sun am...he forgot to tighten a rocker bolt on the pass side, which on his way home caused the other bolt to shear off and and dislodge the push rod from the rocker. he pretty much drove 2 hrs on 7 cylinders...thats why im thinking it was installers error...but i want to be sure for my knowledge.

he has never worked on anything like this, and most people that were here have and helped him when he needed it, but he reinstalled almost everything

 

[BigAlsPSD]

I know a few that were there helping, I have all the faith in the world that they intended to seat them properly, mistakes do happen though. I'm feel it is highly likely that it was simply not seated correctly, I agree that it is difficult to "miss" the lifter, but it is possible.

 

[brownie83]

they are great guys...again, just wanted to do a little brainstorming and see what possibilities are out there to cause this...but after these responses...i think the assembly error is the only possible option
thanks again everyone

 

[Powerstroked162]

no thats the one...but we found out after fixing it sat day, nite and into sun am...he forgot to tighten a rocker bolt on the pass side, which on his way home caused the other bolt to shear off and and dislodge the push rod from the rocker. he pretty much drove 2 hrs on 7 cylinders...thats why im thinking it was installers error...but i want to be sure for my knowledge.

he has never worked on anything like this, and most people that were here have and helped him when he needed it, but he reinstalled almost everything

Wait, the rocker arm carrier sheared off and he drove it like that?? Same cylinder as the bent pushrod this go round??

 

[brownie83]

not the same cylinder. i dont think its the carrier...just the bolt. i haven't seen it, but in his explaination, he told me "both push rods on the pass side #2 cylinder were out of the rockers and the bolts were finger tight." then he realized that one of the "loose" bolts was actually broke off. there was no banging, but he said it didnt have a lot of power and used a lot of fuel?? again, he installed ALL those push rods for round 2 and also torqued all the rockers down...well i guess not all the rockers. i had him pull all the rods to check for straightness, but he decided to just buy 16 new ones to replace all.

NOW...the bolt is broke in the head, and he cannot get a drill to bite into it. last nite when he texted me, he said it was going to a shop on a rollback...have not heard since.